1. Field of the Invention
The invention concerns a steering column module. In particular, the invention concerns a motor vehicle steering column module containing at least two functional modules arranged adjacent to one another in the axial direction of the steering column, and an electronic module which is intended to make contact with the functional modules arranged in the different planes by means of plug-and-socket connectors and also to connect them to the vehicle electrical system, with the one part of each plug-and-socket connector being assigned to one functional module and the one cooperating with it being assigned to the electronic module.
2. Background Art
As a rule, motor vehicle steering column modules consist of several individual functional modules, such as, for example, steering column switches, a contact coil cassette, a steering angle sensor device, etc. These functional modules are arranged in different planes above one another in the axial direction of the steering column, and surround it. The steering column""s casing tube also has a steering column lock fastened to it. An ignition switch can be a functional module that is part of a steering column module. The functional modules also have an electronic module assigned to them, which makes contact with the individual functional modules and which connects the functional modules to the vehicle electrical system. In addition, the power electronics of the functional modules can be arranged on the electronic board.
To make it easier to assemble such a steering column module, the individual functional modules make electrical contact with the electronic module through plug-and-socket connectors, one part of each of which is assigned to a functional module with which contact is supposed to be made, and the complementary part cooperating with the first part is assigned to the electronic module. In a previously known embodiment, such as for example that disclosed in EP 0 853 022 A1, the electronic module forms its own plane in the structure of the steering column module, and thus is integrated in the stratified structure of the functional module. In this previously known embodiment, the electronic module forms a lowest plane, which has several steering column switches arranged on it in a first functional module plane lying above it. The adjacent arrangement makes it easy for there to be direct contact between the switches and the electronic module. Another plane above the plane of the steering column switches has a contact coil cassette arranged in it. In order that this can also make contact through the electronic module, it has an elongated extension which reaches through the arrangement of steering column switches into the plane of the electronic module, so that it can be inserted into one part of a plug-and-socket connector of the electronic module.
Although this previously known steering column module can have several functional modules arranged in different planes make electrical contact with the electronic module, it requires that the functional modules not directly bordering the electronic module reach through the others. To accomplish this, the functional modulesxe2x80x94both those which are supposed to make contact with the electronic module and those through which the contact must passxe2x80x94have to be specially designed. This absolute need for steering column modules to be coordinated on top of one another makes it difficult to make steering column modules whose functional modules can be combined according to a modular principle to form a steering column module which meets the appropriate specifications. The fact that the functional modules that are not adjacent to the electronic module reach through other functional modules especially limits the space in this functional module plane that is available for the other functional modules. If it is desired to provide a connection to the electronic module for functional modules which must reach through two or more functional module planes, this is only possible with excessive effort.
Starting from the prior art which has been discussed, the invention is therefore based on the task of further developing a motor vehicle steering column module of the type mentioned at the beginning so as to avoid the disadvantages shown for the prior art.
This task is solved according to the invention by the fact that plug-and-socket connector parts of the functional modules, which are provided for the electronic module to make contact, are arranged so that their longitudinal extension is radial or tangential to the steering column, and the electronic module is arranged on the functional modules so that the plug-and-socket connector parts assigned to it are on the outside and so that the electronic module engages with the plug-and-socket connector parts.
In the steering column module according to the invention, in contrast to the previously known prior art, the electronic module is not part of the stratified structure, but rather extends transverse to the stratified arrangement of functional module planes. Consequently, depending on the design of the electronic module, it is possible for a virtually unlimited number of functional modules arranged in different planes relative to the longitudinal axis of the steering column to make contact, without the functional modules having to reach through one another to do so. Each functional module plane has, for the functional modules which are to make contact, at least one plug-and-socket connector part arranged so that its longitudinal extension is radial or tangential to the longitudinal axis of the steering column. The plug-and-socket connectors are on the outside of the functional modules which are to make contact, so that pushing on or putting on the electronic module simultaneously makes contact with all functional modules. The peripheral arrangement of the electronic module is also especially advantageous with regard to the interchangeability of the electronic module or for repair purposes, since the structure of functional modules on top of one other does not have to be taken apart.
It is expedient for the electronic module to be held in a housing, which can have means of attachment on it to fasten the housing on the functional modules. For example, such attachment can be implemented by the use of snap-on devices which act like clips. This means that the electronic module or its housing can also be used to implement the fixing of the functional modules in different planes to one another. The electronic module does not need any additional space in the axial direction relative to the steering column""s longitudinal axis. As it is, this space is very limited, since steering column modules are having an increasing number of functional modules integrated into them. The electronic module lying against the functional modules on the outside can be arranged, for example, with its housing on the side of a steering column module facing the floor of a motor vehicle.
An expedient embodiment of such a steering column module also has a lock body of a steering column lock integrated into it, which is fastened to the steering column""s casing tube. Although this lock body does not itself represent a functional module, in this embodiment it acts as a carrier for the functional modules which are arranged in layers on top of one another. This arrangement saves more free space in the axial direction, since the previously known prior art for attaching the functional modules uses separate carriers that are individually fastened to the casing tube.
Another embodiment provides that the electronic module has extensions which can fold out of the actual assembly plane, which is arranged parallel to the steering column, into the plane of the functional modules. Such extensions can, for example, grasp the top and bottom functional modules, so that it is also possible for them to make contact in the axial direction. In such a case the electronic module itself can be made, for example, in the form of a flexible, partially stiffened circuit board, so that connection of additional circuit board conductors is not necessary.